#include <stdio.h>
int main(void) 
{
	double x,y;
	x=2.0;
	y=5.0;
	printf("x+y=%lf\n",x+y);
	printf("x-y=%lf\n",x-y);
	printf("x*y=%lf\n",x*y);
	printf("y/x=%lf\n",y/x);
	return 0;
}
